Robot cleaner

Abstract

A robot cleaner including: a cleaner body; a motor, configured to be fixed to the cleaner body, and provide a rotational force; a gear unit configured to transmit the rotational force of the motor; a wheel configured to rotate and drive the cleaner body according to the rotational force of the motor transmitted by the gear unit to the wheel; and a suspension including a first end portion pivotally supportable on a pivot of the cleaner body, which is spaced apart from a rotary shaft of the motor, and a second end portion to extend from the first end portion and support the wheel to move up and down with respect to the cleaner body as the second end portion moves in a first direction and a second direction around the pivot of the cleaner body.

What is claimed is: 
     
       1. A robot cleaner comprising:
 a cleaner body; 
 a motor, configured to be fixed to the cleaner body, and provide a rotational force; 
 a gear unit configured to transmit the rotational force of the motor; 
 a wheel configured to rotate and drive the cleaner body according to the rotational force of the motor transmitted by the gear unit to the wheel; and 
 a suspension comprising:
 a first end portion pivotally supportable on a pivot of the cleaner body, which is spaced apart from a rotary shaft of the motor, and 
 a second end portion to extend from the first end portion and support the wheel to be moveable relative to the cleaner body while the motor is fixed to the cleaner body whereby the wheel moves up with respect to the cleaner body as the second end portion moves in a first direction around the pivot of the cleaner body and the wheel moves down with respect to the cleaner body as the second end portion moves in a second direction around the pivot of the cleaner body, 
 wherein an axis of the pivot of the cleaner body is horizontally located between the rotary shaft of the motor supported on the cleaner body and a lower end of the cleaner body, and closer to the lower end of the cleaner body than the rotary shaft. 
 
 
     
     
       2. The robot cleaner of  claim 1 , wherein the gear unit comprises a first gear unit provided between the rotary shaft of the motor and the pivot of the cleaner body, and a second gear unit provided between the pivot of the cleaner body and a wheel shaft of the wheel. 
     
     
       3. The robot cleaner of  claim 2 , wherein the first gear unit comprises a reduction gear. 
     
     
       4. The robot cleaner of  claim 2 , wherein the first gear unit comprises:
 a first gear supportable on the rotary shaft of the motor; 
 a second gear supportable on the pivot of the cleaner body; and 
 a third gear supportable on the cleaner body to rotate engaging with the first gear and the second gear. 
 
     
     
       5. The robot cleaner of  claim 4 , wherein
 the third gear comprises a third lower gear and a third upper gear which are coaxially and integrally supportable thereon, and 
 the third lower gear engages with the first gear, and the third upper gear engages with the second gear. 
 
     
     
       6. The robot cleaner of  claim 3 , wherein the second gear unit comprises:
 a fourth gear coaxially and integrally supportable thereon; 
 a fifth gear supportable on the wheel shaft; and 
 a sixth gear, a seventh gear and an eighth gear provided to sequentially engage between the fourth gear and the fifth gear. 
 
     
     
       7. The robot cleaner of  claim 6 , wherein
 the seventh gear comprises a seventh lower gear and a seventh upper gear which are coaxially and integrally supportable thereon, and 
 the eighth gear comprises an eighth lower gear and an eighth upper gear which are coaxially and integrally supportable thereon. 
 
     
     
       8. The robot cleaner of  claim 7 , wherein
 the sixth gear engages with both the fourth gear and the seventh lower gear, 
 the seventh upper gear engages with the eighth lower gear, and 
 the eighth upper gear engages with the fifth gear. 
 
     
     
       9. The robot cleaner of  claim 1 , wherein the suspension comprises a tension spring comprising opposite ends that are supportable on the suspension and the cleaner body, and elastically stretched and compressed as the pivot turns. 
     
     
       10. The robot cleaner of  claim 9 , wherein
 the suspension comprises a first hook supporter provided in the first end portion thereof and is configured to hook a first end of the tension spring, and 
 the cleaner body comprises a second hook supporter configured to hook a second end of the tension spring. 
 
     
     
       11. The robot cleaner of  claim 10 , wherein
 the cleaner body comprises a suspension case to accommodate and cover the suspension, 
 the first hook supporter is configured to pass through and protrude from a first side of the suspension case, and 
 the second hook supporter is supportable on a second side of the suspension case. 
 
     
     
       12. The robot cleaner of  claim 10 , further comprising:
 a lift detector provided within a turning radius of the first hook supporter corresponding to pivoting of the suspension, and configured to detect a lift of the wheel with respect to the cleaner body. 
 
     
     
       13. The robot cleaner of  claim 12 , wherein the lift detector comprises:
 an actuator to support a magnet and be supportable to turn by the turning of the first hook supporter; and 
 a magnet sensor provided in the cleaner body within a turning path of the actuator. 
 
     
     
       14. The robot cleaner of  claim 1 , wherein the cleaner body has a center of gravity at a front side thereof with respect to a center of the wheel.